IDXX insider Mazelsky sells 29,260 shares after option exercise

Rhea-AI Filing Summary

Jonathan Jay Mazelsky, President and CEO and a director of IDEXX Laboratories (IDXX), reported a series of transactions dated 08/06/2025. He acquired 29,260 shares by exercising non-qualified stock options at an exercise price of $67.85 per share and sold a matching total of 29,260 common shares the same day in multiple tranches at reported weighted-average prices between $626.9024 and $639.3718 per share. The reported sales reduced his direct holdings from 112,571.3016 shares to 83,311.3016 shares. Based on the reported quantities and prices, the aggregate gross proceeds from the sales are approximately $18.49 million. The filing also references an option grant to buy 41,260 shares that became exercisable in five annual installments beginning 02/14/2017.

Positive

• Clear transparency: The Form 4 discloses all quantities, tranche-weighted prices and resulting ownership figures.
• Substantial retained stake: After transactions, Mazelsky still directly owns 83,311.3016 shares.

Negative

• Large insider sell: A total of 29,260 shares were sold on 08/06/2025, equal to the number acquired that day.
• Significant gross proceeds: The disclosed sales generated approximately $18.49 million in aggregate proceeds, materially reducing reported direct holdings from 112,571.3016 to 83,311.3016 shares.

Insights

Corporate Governance Expert

TL;DR: CEO exercised options and sold the acquired shares same day; he remains a significant shareholder with 83,311.3016 shares.

The Form 4 shows a same-day exercise of 29,260 optioned shares at $67.85 and matching sales that reduced direct beneficial ownership from 112,571.3016 to 83,311.3016 shares. From a governance perspective, the filing documents a material CEO transaction and preserves transparency by disclosing quantities, prices and resulting ownership. The continued holding of 83,311.3016 shares indicates ongoing direct ownership, while the disclosed option grant (41,260 shares exercisable in installments beginning 02/14/2017) remains on the record.

Securities Analyst

TL;DR: The reported sales of 29,260 shares generated roughly $18.49M in gross proceeds on 08/06/2025.

Using the per-tranche quantities and reported weighted-average prices in the filing, the ten sale tranches totaling 29,260 shares produced aggregate gross proceeds of approximately $18.49 million. The exercise price for the acquired shares was $67.85, documented in the filing. The transaction sequence—exercise followed by multiple sales the same date—materially changed reported direct ownership levels and is fully itemized in the Form 4.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

MAZELSKY JONATHAN JAY

(Last) (First) (Middle)

ONE IDEXX DRIVE

(Street)

WESTBROOK ME 04092

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
IDEXX LABORATORIES INC /DE [ IDXX ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	President and CEO

3. Date of Earliest Transaction (Month/Day/Year)
08/06/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	08/06/2025		M		29,260	A	$67.85	112,571.3016(1)	D
Common Stock	08/06/2025		S		1,095	D	$626.9024(2)	111,476.3016	D
Common Stock	08/06/2025		S		1,525	D	$628.272(3)	109,951.3016	D
Common Stock	08/06/2025		S		3,397	D	$629.8228(4)	106,554.3016	D
Common Stock	08/06/2025		S		6,056	D	$630.5935(5)	100,498.3016	D
Common Stock	08/06/2025		S		7,299	D	$631.6065(6)	93,199.3016	D
Common Stock	08/06/2025		S		3,000	D	$632.563(7)	90,199.3016	D
Common Stock	08/06/2025		S		3,526	D	$635.1268(8)	86,673.3016	D
Common Stock	08/06/2025		S		1,822	D	$636.1517(9)	84,851.3016	D
Common Stock	08/06/2025		S		880	D	$636.8083(10)	83,971.3016	D
Common Stock	08/06/2025		S		660	D	$639.3718(11)	83,311.3016	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Non-Qualified Stock Option (right-to-buy)	$67.85	08/06/2025		M			29,260	(12)	02/13/2026	Common Stock	29,260	(13)	0	D

Explanation of Responses:

1. Includes 28.7090 shares purchased under the Issuer Employee Stock Purchase Plan on March 31, 2025 and June 30, 2025.

2. Represents the weighted average price of the shares sold ranging from a low of $626.585 to a high of $627.44 per share. The undersigned undertakes, upon request by the Commission staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares purchased at each separate price.

3. Represents the weighted average price of the shares sold ranging from a low of $627.72 to a high of $628.71 per share. The undersigned undertakes, upon request by the Commission staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares purchased at each separate price.

4. Represents the weighted average price of the shares sold ranging from a low of $629.14 to a high of $630.06 per share. The undersigned undertakes, upon request by the Commission staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares purchased at each separate price.

5. Represents the weighted average price of the shares sold ranging from a low of $630.14 to a high of $630.885 per share. The undersigned undertakes, upon request by the Commission staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares purchased at each separate price.

6. Represents the weighted average price of the shares sold ranging from a low of $631.26 to a high of $632.15 per share. The undersigned undertakes, upon request by the Commission staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares purchased at each separate price.

7. Represents the weighted average price of the shares sold ranging from a low of $632.41 to a high of $633.30 per share. The undersigned undertakes, upon request by the Commission staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares purchased at each separate price.

8. Represents the weighted average price of the shares sold ranging from a low of $634.66 to a high of $635.64 per share. The undersigned undertakes, upon request by the Commission staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares purchased at each separate price.

9. Represents the weighted average price of the shares sold ranging from a low of $635.66 to a high of $636.53 per share. The undersigned undertakes, upon request by the Commission staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares purchased at each separate price.

10. Represents the weighted average price of the shares sold ranging from a low of $636.66 to a high of $637.39 per share. The undersigned undertakes, upon request by the Commission staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares purchased at each separate price.

11. Represents the weighted average price of the shares sold ranging from a low of $639.235 to a high of 639.49 per share. The undersigned undertakes, upon request by the Commission staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares purchased at each separate price.

12. Grant of option to buy 41,260 shares of Issuer common stock that became exercisable in five annual installments beginning February 14, 2017.

13. Not applicable

Remarks:

	/s/ Lily J. Lu, Attorney-in-Fact for Jonathan Jay Mazelsky	08/08/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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FAQ

What transactions did IDXX CEO Jonathan Mazelsky report on 08/06/2025?

He exercised 29,260 optioned shares at $67.85 per share and sold 29,260 common shares in multiple tranches the same day.

How many shares does Mazelsky own after the reported transactions?

Following the transactions he directly beneficially owns 83,311.3016 shares, down from 112,571.3016 shares before the sales.

What were the sale prices reported for the share tranches?

Reported weighted-average sale prices by tranche range from $626.9024 to $639.3718 per share across the disclosed sales.

What were the aggregate proceeds from the sales?

Based on the filing’s quantities and reported weighted-average prices, aggregate gross proceeds are approximately $18.49 million.

Does the filing reference other option grants?

Yes. The filing notes a grant of options to buy 41,260 shares that became exercisable in five annual installments beginning 02/14/2017.